The purpose of this research study is to find out whether preterm infants are receiving enough of the essential and long chain fatty acids important for brain development and immune function. Our current intravenous (IV) fats do not contain the long chain fatty acids and different milk sources have different compositions. We would like to evaluate lactating mothers dietary intake and breastmilk level of fatty acid status by doing an analysis of their blood and breastmilk samples after they have been supplemented with a currently used fatty acid supplement (DHA- Martek Biosciences, now known as Dutch State Mines (DSM) Nutritional Lipid) The DHA supplement is available over the counter.